Increasing the average age of your employees is a much smaller change to make to your company than, for example, hiring remote people (assuming you aren't already doing that). Even if you're currently the all-work-no-life 80-hours-a-week always-crunch-time kind of company, if you really have trouble finding the right talent, there's an option right there for you. It requires more sane working hours, yes, but maybe that's not a horribly bad idea anyway.
People not even considering this are doing themselves a disservice.
Anecdotally, I have found the argument that not-super-young people are somehow less smart or less eager to be entirely false.